byteify-strings: add --treat-as-kwargs argument to handle kwargs-like objects
This argument will help extensions move to Python 3 as keyword arguments
should not be byte-prefixed. Most of the time, code bases will call this
object `kwargs`, but other conventions exist like `opts`, so it should make
sense to allow for custom names.
This is a best effort solution that does minimal static checking; cases like
`options = [o for o in ('a', 'b', 'c') if kwargs.get(o)]`
and other just as complicated will not be detected.
$ hg init empty-repo
$ cd empty-repo
Flags on revlog version 0 are rejected
>>> with open('.hg/store/00changelog.i', 'wb') as fh:
... fh.write(b'\x00\x01\x00\x00') and None
$ hg log
abort: unknown flags (0x01) in version 0 revlog 00changelog.i!
[255]
Unknown flags on revlog version 1 are rejected
>>> with open('.hg/store/00changelog.i', 'wb') as fh:
... fh.write(b'\x00\x04\x00\x01') and None
$ hg log
abort: unknown flags (0x04) in version 1 revlog 00changelog.i!
[255]
Unknown version is rejected
>>> with open('.hg/store/00changelog.i', 'wb') as fh:
... fh.write(b'\x00\x00\x00\x02') and None
$ hg log
abort: unknown version (2) in revlog 00changelog.i!
[255]
$ cd ..
Test for CVE-2016-3630
$ hg init
>>> import codecs
>>> open("a.i", "wb").write(codecs.decode(codecs.decode(
... b"""eJxjYGZgZIAAYQYGxhgom+k/FMx8YKx9ZUaKSOyqo4cnuKb8mbqHV5cBCVTMWb1Cwqkhe4Gsg9AD
... Joa3dYtcYYYBAQ8Qr4OqZAYRICPTSr5WKd/42rV36d+8/VmrNpv7NP1jQAXrQE4BqQUARngwVA==""",
... "base64"), "zlib")) and None
$ hg debugrevlogindex a.i
rev linkrev nodeid p1 p2
0 2 99e0332bd498 000000000000 000000000000
1 3 6674f57a23d8 99e0332bd498 000000000000
>>> from mercurial import revlog, vfs
>>> tvfs = vfs.vfs(b'.')
>>> tvfs.options = {b'revlogv1': True}
>>> rl = revlog.revlog(tvfs, b'a.i')
>>> rl.revision(1)
mpatchError(*'patch cannot be decoded'*) (glob)